1. Field of the Invention
This invention relates to a high-performance semiconductor component with a disc-shaped body, having at least one pn-junction, with thermically and electrically conductive heat dissipation discs, in the main current and thermal paths, soldered to the corresponding contact surfaces of the semiconductor body by way of equally thermically and electrically conductive disc-shaped metal contacts, and with an insulating housing surrounding the disc rim of the semiconductor disc.
2. Description of the Prior Art
A high-performance semiconductor component of this type may be used as an individual element, or it may be integrated into a high-performance semiconductor module for the assembly of rectifier circuits. The term "high-performance semiconductor-module", here, is to be understood to mean an element with one or several, preferably, however, two semiconductor elements fastened to a common mounting plate, in the form of tablets provided with electrodes, insulated or passivized, respectively, along their rims, frequently not having a housing and, as an alternative, with wiring elements contained in a common housing with a cooling device, whereby the main current connections and the gate current connections, where applicable, of the semiconductor element or elements, preferably are brought out of the housing at one side only. It is known, however, that so-called disc-cells, which are high-capacity semiconductor elements with their own disc-shaped housing, may be integrated into a module (BBC-Communications 1978, pp. 200-206).
For the thermic and electrical contacting of high-performance semiconductor components, at present, mainly dotting contact technology is utilized (VDE-Book Series, Vol. 11 (1966), p. 84). The dotting contact technology may be combined with advanced solutions, as, for instance, the use of heat pipes, or of direct water cooling, with great difficulty. Also, heat elimination by way of a dotting contact must be considered to be a compromise from the beginning because of the differences in thermic expansion of the materials used. In instances of pure dotting contact technology, i.e. with contacts between all heat-transfer surfaces and the cooling elements, the insertion of ductile silver cups is of record (DE-OS No. 2 029 806). For this, and additional embodiments of dotting contact technology of record, it must be observed that two surfaces are sliding directly upon each other and that the effects of friction must be anticipated. With increasing disc diameters, dotting contact technology is reaching its limits because of the increasing absolute differences of radial expansion and the increasing difficulties of uniform distribution of pressure.
Numerous variances of pure dotting contact technology are known, which means that contacts between the semiconductor body, the metal discs and the heat dissipation plates, mostly made of copper or molybdenum, are also often designed to partially utilize close fitting material contact (i.e., DE-OS No. 1 944 081). Because of differences in thermic expansion, the size of such soldered contacts is limited.
An additional solution is of record, whereby liquid metal contacts are provided (U.S. Pat. No. 3,654,528, GB-PS No. 914 034). This technology has problems with sealing tightness, with corrosive influences of the liquid metal and difficulties with stress caused by temperature variations.